Heat pump laundry treatment apparatus and method of operating a heat pump laundry treatment apparatus

A method of operating a heat pump laundry treatment apparatus, wherein the laundry treatment apparatus includes:

• a control unit controlling an operation of the laundry treatment apparatus,
• a laundry treatment chamber for treating laundry using process air,
• a process air circuit for circulating the process air,
• a heat pump system having a refrigerant loop in which refrigerant fluid is circulated through a first and a second heat exchanger,
• a compressor for circulating the refrigerant fluid through the refrigerant loop,
• a cooling fan unit for cooling the compressor, wherein during the operation a conveyance capacity of the cooling fan unit is varied, and
• a detector unit for detecting an operation parameter indicating a state of at least one electronic board of the apparatus,
• the method comprising:
• operating the cooling fan unit based upon the electronic board operation parameter, and
• controlling a compressor operation output based upon the electronic board operation parameter, wherein:
• controlling the operation of the cooling fan unit includes adapting the conveyance capacity of the cooling fan unit based upon the electronic board operation parameter, and
• the conveyance capacity of the cooling fan unit is defined by one or more of a duty cycle ratio of switching the cooling fan unit ON and OFF, and a conveyance rate of the cooling fan unit.